In the Sermon the Mount Jesus made a revolutionary pronouncement. Rather than hate your enemy, “love your enemies and pray for those who harass you” (Matthew 5:44).
Love for enemy for Jesus is grounded in the belief that all of us, friend and foe alike, are children of God who “makes his sun rise on both the evil and the good and sends rain on both the righteous and unrighteous” (Mathew 5:45b). In Luke’s version Jesus says, “Be compassionate just as your Father is compassionate” (Luke 6:36). Therefore, we too should be kind and compassionate to everyone, even those we consider to be our enemies
Jesus further instructs, “Therefore, just as your heavenly Father is complete in showing love to everyone, so also you must be complete” (Matthew 5:43-48). This is the Common English Bible translation. Other versions translate this verse as “Be perfect, therefore, as your heavenly father is perfect.” Barnes’ Notes on the Bible say that the Greek word used commonly means “finished, complete, pure, holy”. We recognize that God loves us. God loves others, too. When we also love others, including our enemies, we complete the circle. A kind of perfection.